Automobiles and other vehicles typically utilize pneumatic tires mounted on a wheel for gripping the surface of the road. Tire over-inflation and under-inflation can lead to uneven tread wear, reduced grip at the tire-to-road contact area, and reduced tire performance. The handling characteristics of a wheeled vehicle are directly related to the amount of friction/grip, both lateral and longitudinal, obtained by the tire-to-road interface. Increased regulation has created the need to monitor the pressure of tires.
Direct tire pressure monitoring systems (TPMS) utilize radio frequency (RF) transmitters that are located in each wheel/tire assembly. Each sensor typically contains a unique identification (ID) code with its own RF data stream that is learned by the receiving electronic device to allow the TPMS to properly interpret each sensor's data by its physical location on the vehicle. Relearning is required in the factory when the tires are installed, when the customer alters sensor locations (rotate wires, change flat), or when a damaged sensor has been replaced. Existing auto-locations systems permit the learning operation to occur automatically without customer intervention, however these systems these systems require specialized hardware and are not cost effective.